private:
friend class boost::serialization::access;
template<typename Archive>
void serialize(Archive& ar, const unsigned int version)
{
ar & BOOST_SERIALIZATION_NVP(name_);
ar & BOOST_SERIALIZATION_VP(number_);
ar & BOOST_SERIALIZATION_NVP(grade_);
}其实这个函数相当于两个函数：但我们使用xxx_oarchive时它等价于把对象数据save到文档中，template<typename Archive>
void save(Archive& ar, const unsigned int version) const
{
ar << BOOST_SERIALIZATION_NVP(name_);
ar << BOOST_SERIALIZATION_NVP(number_);
ar << BOOST_SERIALIZATION_NVP(grade_);
}load函数:template<typename Archive>
void load(Archive& ar, const unsigned int version)
{
ar >> BOOST_SERIALIZATION_NVP(name_);
ar >> BOOST_SERIALIZATION_NVP(number_);
ar >> BOOST_SERIALIZATION_NVP(grade_);
}最后需要加上一个宏：BOOST_SERIALIZATION_SPLIT_MEMBER() //must be part of class这个宏必须是在类的内部。其实这个宏实现了一个模版函数：
#define BOOST_SERIALIZATION_SPLIT_MEMBER() template<class Archive> void serialize( Archive &ar, const unsigned int file_version ){ boost::serialization::split_member(ar, *this, file_version); } 就是调用一个split_member函数，这个函数在头文件split_member.hpp中：template<class Archive, class T>
inline void split_member(
Archive & ar, T & t, const unsigned int file_version
)
{
typedef BOOST_DEDUCED_TYPENAME mpl::eval_if<
BOOST_DEDUCED_TYPENAME Archive::is_saving,
mpl::identity<detail::member_saver<Archive, T> >,
mpl::identity<detail::member_loader<Archive, T> >
>::type typex;//#1
typex::invoke(ar, t, file_version);
}#1使用traits技术推导出type类型，实际上这个type只有两种类型template<class Archive, class T>
static void member_save(Archive & ar,
//const T & t,
T & t,
const unsigned int file_version
)
{
t.save(ar, file_version);//access类成员函数member_save,由此可见boost设计模式很复杂，但是值得学习
}
friend class boost::serialization::access;
//我们的save和load代码这样access就可以调用我们写的save和load代码了。class student_info
{
public:
student_info() {}
virtual ~student_info() {}
student_info(const std::string& sn, const std::string& snm, const std::string& sg, const std::string& cs)
: name_(sn), number_(snm), grade_(sg), class_(cs)
{
}
virtual void print_info() const
{
std::cout << name_ << " " << number_ << " " << grade_ << " " << class_ << " ";
}
private:
//friend class boost::serialization::access;
/*
template<typename Archive>
void serialize(Archive& ar, const unsigned int version)
{
ar & BOOST_SERIALIZATION_NVP(name_);
ar & BOOST_SERIALIZATION_VP(number_);
ar & BOOST_SERIALIZATION_NVP(grade_);
}
*/
friend class boost::serialization::access;//友元类这样它的成员函数member_save(load)就可以调用我们自己实现的save、load
template<typename Archive>
void save(Archive& ar, const unsigned int version) const
{
ar << BOOST_SERIALIZATION_NVP(name_);
ar << BOOST_SERIALIZATION_NVP(number_);
ar << BOOST_SERIALIZATION_NVP(grade_);
ar << BOOST_SERIALIZATION_NVP(class_);
}
template<typename Archive>
void load(Archive& ar, const unsigned int version)
{
ar >> BOOST_SERIALIZATION_NVP(name_);
ar >> BOOST_SERIALIZATION_NVP(number_);
ar >> BOOST_SERIALIZATION_NVP(grade_);
}
BOOST_SERIALIZATION_SPLIT_MEMBER() //must be part of class
private:
std::string name_;
std::string number_;
std::string grade_;
};
class student_info
{
public:
//...
private:
friend class boost::serialization::access;
template<typename Archive>
void serialize(Archive& ar, const unsigned int version)
{
ar & BOOST_SERIALIZATION_NVP(name_);
ar & BOOST_SERIALIZATION_VP(number_);
ar & BOOST_SERIALIZATION_NVP(grade_);
}
private:
std::string name_;
std::string number_;
std::string grade_;
};这个函数是intrusive的，我们也可以用一种non-intrusive：class student_info
{
public:
//...
private:
template<typename Archive>
friend void serialize(Archive& ar, student_info &sdinfo, const unsigned int file_version);
private:
std::string name_;
std::string number_;
std::string grade_;
};再类外面实现 serialize 函数：template<typename Archive>
void serialize(Archive& ar, student_info &sdinfo, const unsigned int file_version)
{
ar & BOOST_SERIALIZATION_NVP(sdinfo.name_);
ar & BOOST_SERIALIZATION_NVP(sdinfo.number_);
ar & BOOST_SERIALIZATION_NVP(sdinfo.grade_);
}这样就ok了。boost::serialization 拆分serialize函数,布布扣,bubuko.com
boost::serialization 拆分serialize函数
原文地址：http://blog.csdn.net/xiaoliangsky/article/details/25003791
